"I think that Apple could be just as strong and good and be open, but how can you challenge it when a company is making that much money?", Wozniak told a crowd in Sydney, according to ITNews. They'd score so many brownie points the internet would explode.

I'd be interesting to hear what the reason is.
If you modify the device you void your warranty, nothing else needs to happen. It doesn't tarnish anyone's brand or some such nonsense. Please note that I don't count what moronic managers *think* will happen as a rational reason.

If you modify your car or phone and make a complete mess of it, that's no problem (well, it is for you personally of course).

If you allow people, most of which aren't technical savvy, to install whatever they want on a class of devices that's currently targeted by cyber criminals an increasing number of users will experience problems and/or become victims. It would destroy the image of the device, in this case the iPhone, of being "safe" and "secure", despite if it really is.

When something sticks it can stick for a long time. Like the MessagePad's handwriting recognition which was bad in the first version and pretty good in the last one. Yet, when the MessagePad is mentioned bad handwriting recognition isn't far away from the discussion.

Windows is still associated by many as something that crashes a lot, which it doesn't since Windows 2000.

Apple has build a positive image. The public doesn't even make a fuss of any missteps they make. Antenna gate didn't prevent the iPhone 4 from becoming the best sold phone at the time, OS X is still seen as secure and even Steve is viewed as a great person despite not being very nice a lot of times. Their future products will benefit from this public perception.

Even when a product isn't really that good or original, it will get more than the benefit of the doubt. A lot of great products/ideas have failed because they were brought to market by unknown companies or ones that didn't have a better name than their competitors.

A large number would pick an Apple iPhone over a Windows Phone just based on the familiarity and brand image of Apple. Most people don't look at specs, stats or reviews.